Information processing apparatus for updating environment information

ABSTRACT

According to an aspect of an embodiment, a server apparatus connected to a plurality of client apparatuses capable of sending out a message containing environment information to the server apparatus, the server apparatus has a storage for storing environment information in association with each of the client apparatuses and a processor for receiving a message including updated environment information indicative of addition of an interface device connected to the client apparatus from the client apparatus and for updating the environment information in the storage with the updated environment information.

BACKGROUND

The present technique relates to communication in redundancy managementLAN (local area network) environments in network systems for businessentities and so on. The present technique relates to a communicationmanagement program for causing a computer to execute processing formanaging communication with client apparatuses through a network and forresponding to a predetermined request received from each clientapparatus and also to a communication management method and acommunication management apparatus which implement the communicationmanagement program.

In order to improve the management efficiency through computerization ofcorrespondence and so on in business activities, network systems, suchas LANs (e.g., Japanese Unexamined Patent Application Publication No.2003-273885) is build. When a LAN is installed in a business entity as anetwork system, it is common to provide the LAN with redundancy for, forexample, a network-system downtime due to a failure.

A known technology for a redundancy management LAN will be brieflydescribed with reference to FIG. 7. As illustrated in FIG. 7, a clientapparatus is quipped with redundancy LAN cards, which include a LAN cardA 102 (e.g., LAN A) that is usually used for communication through a LANand a LAN card B 104 (e.g., LAN B) that is used, through switching, forcommunication with a management server when the LAN card A fails.

The management server shown in FIG. 7 pre-registers, in a managementtable, a MAC (media access control) address (e.g., MAC A 202) associatedwith the LAN card A that is usually used by the client apparatus.

For example, upon receiving a PXE (Preboot execution Environment)startup request or the like from the client apparatus, the managementserver determines whether or not a MAC address indicating thetransmission source of the request is already registered in themanagement table. When the MAC address indicating the transmissionsource and the MAC address registered in the management table match eachother, the management server responds to the request, and when the MACaddresses do not match each other, the management server rejects therequest.

There is a Japanese Laid-open Patent Publication No. 2003-273885.

However, in the known technology, the management server cannot respondto a case in which switching between LAN cards is performed at theclient apparatus, and thus has a problem of rejecting a request from theclient apparatus.

That is, as shown in FIG. 8, when the LAN card A fails, the clientapparatus performs switching from the LAN card A to the LAN card B andtransmits, to the management server, a request for permitting the LANcard B as a transmission source. Upon receiving the request from theclient apparatus, however, the management server rejects the requestfrom the client, when a MAC address (e.g., MAC B 204) indicating thetransmission source of the request does not match a MAC address (e.g.,MAC A) registered in the management table. The known technology,therefore, has a problem in that communication may not be establishedbetween the management server and the client apparatus.

SUMMARY

According to an aspect of an embodiment, a server apparatus connected toa plurality of client apparatuses capable of sending out a messagecontaining environment information to the server apparatus, the serverapparatus has a storage for storing environment information inassociation with each of the client apparatuses and a processor forreceiving a message including updated environment information indicativeof addition of an interface device connected to the client apparatusfrom the client apparatus and for updating the environment informationin the storage with the updated environment information.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an overview and a feature of amanagement server according to a first embodiment;

FIG. 2 is a block diagram showing the configuration of the managementserver according to the first embodiment;

FIG. 3 is a table showing an example of the configuration of themanagement table according to the first embodiment;

FIG. 4 is a sequence diagram showing the flow of MAC-addressregistration processing according to the first embodiment;

FIGS. 5A and 5B are sequence diagrams showing the flow of responseprocessing according to the first embodiment;

FIG. 6 is a diagram showing a computer for executing a communicationmanagement program;

FIG. 7 is a diagram illustrating a known technology; and

FIG. 8 is a diagram illustrating the known technology.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A communication management program, a communication management method,and a communication management apparatus according embodiments of thepresent technique will be described below with reference to theaccompanying drawings. A management server to which a communicationmanagement program according to the present technique is applied willfirst be described in a first embodiment and other embodimentsencompassed by the present technique will then be described.

First Embodiment

An overview and features of a management server according to a firstembodiment, the configuration of the management server, the processingof the management server and advantages of the first embodiment will bedescribed below in that order.

Overview and Features of Management Server:

Firstly, an overview and features of the management server according tothe first embodiment will be described with reference to FIG. 1. FIG. 1is a diagram illustrating an overview and a feature of the managementserver according to the first embodiment.

An overview of the management server according to the first embodimentis that the management server performs processing for managingcommunication with each client apparatus through a network and forresponding to a predetermined request received from the clientapparatus. A main feature of the management server is that themanagement server can perform operation corresponding to switchingbetween LAN cards in the client apparatus and can respond to a requestfrom the client apparatus.

The main feature will now be described in more detail. As shown in FIG.1, the management server is connected to a client apparatus through aLAN (local area network) 1 so as to allow communication.

The client apparatus transmits, for examples a request for staring a PXE(Preboot execution Environment) to the management server. The clientapparatus is equipped with a LAN card A (LAN A) and a LAN card B (LANB). The LAN card A and the LAN card B are uniquely assignedcorresponding MAC addresses (e.g., MAC A and MAC B), which are used bythe client apparatus to communicate with the management server.

The management server has a management table for pre-storing theredundancy MAC addresses in association with the client apparatus. TheMAC addresses are used when the client apparatus performs datatransmission/reception. With this arrangement, even when one LAN cardthat is currently used by the client apparatus fails and switching tothe other redundant LAN card is performed, the management server canexecute response processing that corresponds to a request from theclient apparatus in real time.

In practice, however, a LAN card having a MAC address other than the MACaddresses pre-stored in the management table included in the managementserver may be newly equipped in the client apparatus Thus, a descriptionwill be briefly given of processing of the management server when a newMAC address that is not registered in the management table is to beregistered in the management table in association with the clientapparatus.

That is, when a MAC address indicating the transmission source of arequest is not registered in the management server, the managementserver rejects a request from the client apparatus and, from then on,does not communicate therewith. In order to prevent such a situation,the management server sets its operation mode to a registration mode soas to indiscriminately respond to a request (e.g., a PXE request) fromthe client apparatus.

For example, upon receiving a PXE packet for the PXE request from theclient apparatus, the management server analyzes the PXE packet, obtainsa MAC address indicating the transmission source of the PXE packet andchecks whether or not the obtained MAC address is already registered inthe management table.

When the obtained MAC address is not registered in the management tableis confirmed, the management server transmits an agent to the clientapparatus to create a list of the MAC addresses of LAN cards equipped inthe client apparatus and also cases the agent to transmit the createdMAC-address list. Upon receiving the MAC-address list transmitted by theagent, the management server registers all of the received MAC addressesin the management table in association with the client apparatus that isthe transmission source of the PXE packet.

That is, all MAC addresses associated with all LAN cards equipped in theclient apparatus are registered. Thus, for example, during processingbetween the client apparatus and the management server, even when theLAN card A that is currently used by the client apparatus fails andswitching to the inactive redundant LAN card B is performed, themanagement server can register the MAC addresses corresponding to theredundancy LAN cards in the client apparatus and also can respond to arequest from the client apparatus by performing real-time operationcorresponding to the switching between the LAN cards in the clientapparatus without suspension of the processing.

Thus, as in the feature described above, the management server accordingto the first embodiment can perform operation corresponding to theswitching between the LAN cards in the client apparatus and can responseto a request from the client apparatus.

Configuration of Management Server:

The configuration of the management server according to the firstembodiment will now be described with reference to FIG. 2. FIG. 2 is ablock diagram showing the configuration of the management serveraccording to the first embodiment. As shown, a management server 20according to the first embodiment is connected to client apparatuses 10through the LAN 1 so as to allow communication.

As shown in FIG. 2, the management server 20 includes acommunication-control interface unit 21, a storage unit 22 and a controlunit 23. The communication-control interface unit 21 controls acommunication for various types of information exchanged with the clientapparatuses 10. The control unit 23 receives a message including updatedenvironment information indicative of addition of an interface deviceconnected to the client apparatus from the client apparatus and updatesthe environment information in the storage with the updated environmentinformation.

The storage unit 22 stores data and programs required for various typesof processing controlled by the control unit 23. And the storage unit 22particularly includes a management table 22 a according to the presenttechnique. More specifically, as illustrated in FIG. 3, the managementtable 22 a stores target IDs 222, startup IDs 224, MAC addresses 226 andMAC-address lengths 228 in association with each other. The storage unit22 stores environment information in association with each of the clientapparatuses.

The target ID has an arbitrary value assigned by the management server20 during registration of the MAC addresses of the client apparatus 10.The startup ID is information for causing the client apparatus 10 toexecute a predetermined startup operation, and a packet specifying aprocessing description corresponding to the startup ID is exchanged withthe client. For example, startup ID “0” indicates a processingdescription “do nothing”, startup ID “1” indicates a processingdescription “local startup”, and startup ID “2” indicates a processingdescription “PXE startup”. The MAC address is information uniquelyassigned to each LAN card equipped in each client apparatus 10 and iscontained in a packet transmitted when the client apparatus 10 issues arequest to the server apparatus 20. The MAC-address length has a valueindicating the total length of data lengths of all MAC addresses. Thedata lengths of the MAC addresses may respectively be stored.

The control unit 23 has an internal memory for storing required data anda program stating various processing procedures. The control unit 23 andthe internal memory serve as a processing unit for executing varioustypes of processing. According to the present technique, the controlunit 23 includes a data transmitting/receiving unit 23 a, a dataanalyzing unit 23 b, a MAC-address registering unit 23 c and a responseprocessing unit 23 d.

The data transmitting/receiving unit 23 a serves a processing unit forreceiving a packet for a predetermined request (e.g., a PXE request)transmitted from the client apparatus 10 through the LAN 1. Morespecifically, for example, the data transmitting/receiving unit 23 asends out the PXE packet, received from the client apparatus 10, to thedata analyzing unit 23 b. The data transmitting/receiving unit 23 a alsotransmits an agent, received from the data analyzing unit 23 b, to theclient apparatus 10. Upon receiving the MAC-address list transmitted bythe agent, the data transmitting/receiving unit 23 a sends out theMAC-address list to the data analyzing unit 23 b.

The data analyzing unit 23 b serves as a processing unit for analyzingthe packet received from the data transmitting/receiving unit 23 a. Morespecifically, for example, the data analyzing unit 23 b analyzes the PXEpacket received from the data transmitting/receiving unit 23 a, obtainsa MAC address indicating the transmission source of the PXE packet andchecks whether or not the obtained MAC address is already registered inthe management table 22 a.

Upon confirming that the obtained MAC address is not registered in themanagement table 22 a, the data analyzing unit 23 b transmits an agentto the client apparatus 10 via the data transmitting/receiving unit 23 ato create a list of the MAC addresses of the LAN cards equipped in theclient apparatus 10 and causes the agent to transmit the createdMAC-address list. Upon receiving the MAC-address list transmitted by theagent from the data transmitting/receiving unit 23 a, the data analyzingunit 23 b sends out the MAC-address list to the MAC-address registeringunit 23 c. After the MAC-address registering unit 23 c completes theregistration of the MAC addresses, the data analyzing unit 23 b issues arequest to the response processing unit 23 d so as to respond to therequest from the client apparatus 10.

On the other hand, upon confirming that the obtained MAC address isregistered in the management table 22 a and receiving, for example, thePXE packet from the client apparatus 10, the data analyzing unit 23 bissues a request to the response processing unit 23 d so as to respondto the request from the client apparatus 10.

The MAC-address registering unit 23 c servers as a processing unit forregistering the MAC addresses in association with each client apparatus.More specifically, the MAC-address registering unit 23 c registers, inthe management table 22 a, the redundancy MAC addresses used when eachclient apparatus 10 performs data transmission/reception, in associationwith the client apparatus 10. During the registration, an arbitrarilyassigned target ID, a startup ID and a MAC-address length are registeredtogether with MAC addresses.

Upon receiving the MAC-address list from the data analyzing unit 23 b,the MAC-address registering unit 23 c registers all of the received MACaddresses in the management table 22 a in association with thecorresponding client apparatus 10.

The response processing unit 23 d serves as a processing unit forresponding to a predetermined request received from the client apparatus10. More specifically, for example, the response processing unit 23 dreceives, from the data analyzing unit 23 b, a request for responding toa PXE request, and then executes processing for responding to therequest from the client apparatus 10, based on a processing-requestprocedure composed in accordance with pre-registered processing of theclient apparatus.

More specifically, the response processing unit 23 d issues, to theclient apparatus 10, an instruction for the processing-request procedurecomposed by the response processing unit 23 d, for example, aninstruction for causing the client apparatus 10 to operate in order ofpower ON, data backup, rebooting and HDD startup.

Processing for responding to a request from the client apparatus 10 willnow be described with respect to one example of the processing-requestprocedure. For example, for execution of processing for responding to arequest from the client apparatus 10 based on the composedprocessing-request procedure, the response processing unit 23 d firstsets the startup ID in the management table 22 a to “2” and issues apower-ON instruction set for (1) in the processing-request procedure tothe client apparatus 10 via the data transmitting/receiving unit 23 a.

Upon receiving the power-ON instruction from the management server 20,the client apparatus 10 is powered up and transmits a PXE packet to themanagement server 20.

When the management server 20 receives the PXE packet from the clientapparatus 10, the data transmitting/receiving unit 23 a in themanagement server 20 sends out the received PXE packet to the dataanalyzing unit 23 b.

The data analyzing unit 23 b analyzes the PXE packet received from thedata transmitting/receiving unit 23 a, obtains a MAC address indicatingthe transmission source of the PXE packet and checks whether or not theobtained MAC address is already registered in the management table 22 a.

Upon confirming that the obtained MAC address is registered in themanagement table 22 a, the data analyzing unit 23 b issues a request tothe response processing unit 23 d so as to respond to the request fromthe client apparatus 10.

Upon receiving the response-processing request from the data analyzingunit 23 b, the response processing unit 23 d operates in accordance withthe startup ID setted in the management table 22 a and transmits aresponse to the client apparatus 10. That is, the response processingunit 23 d issues a data-backup request set for (2) in theprocessing-request procedure, together with a packet to which startup ID“2” set in the management table 22 a, to the client apparatus 10 via thedata transmitting/receiving unit 23 a.

Upon receiving the data backup request together with the packet from themanagement server 20, the client apparatus 10 performs PXE startup inaccordance with startup ID “2” added to the packet and executes databackup in accordance with the backup instruction. Upon completion of thedata backup, the client apparatus 10 transmits a backup completionnotification to the management server 20.

Upon receiving the backup completion notification from the clientapparatus 10 via the data transmitting/receiving unit 23 a, the responseprocessing unit 23 d in the management server 20 issues a rebootingrequest set for (3) in the processing-request procedure to the clientapparatus 10 via the data transmitting/receiving unit 23 a.

Upon receiving the rebooting request from the management server 20, theclient apparatus 10 starts rebooting. Upon completion of the rebooting,the client apparatus 10 causes an agent to transmit a rebootnotification to the management server 20.

Upon receiving the reboot notification from the client apparatus 10 viathe data transmitting/receiving unit 23 a, the response processing unit23 d in the management server 20 sets the startup ID to “1” and waitsfor reception of a PXE packet from the client apparatus 10.

When a PXE packet is transmitted from the client apparatus 10 to themanagement server 20, the response processing unit 23 d in themanagement server 20 receives the PXE packet via the datatransmitting/receiving unit 23 a. The response processing unit 23 d thenrefers to the management table 22 a and gives a response bytransmitting, to the client 10 via the data transmitting/receiving unit23 a, a packet to which startup ID “1” set for (4) in the processingrequest procedure is added.

Upon receiving the packet from the management server 20, the clientapparatus 10 operates in accordance with the startup ID added to thepacket.

Processing of Management Server:

Processing of the management server according to the first embodimentwill now be described with reference to FIGS. 4 and 5. FIG. 4 is asequence diagram showing the flow of registration processing performedbetween the management server according to the first embodiment and theclient apparatus. FIGS. 5A and 5B are sequence diagrams showing the flowof response processing performed between the management server accordingto the first embodiment and the client apparatus.

Registration Processing:

Firstly, the flow of registration processing performed between themanagement server according to the first embodiment and the clientapparatus will be described with reference to FIG. 4. When a MAC addressindicating the transmission source of a request is not registered in themanagement server, the management server 20 rejects a request from theclient apparatus 10 and, from then on, does not communicate therewith.In order to prevent such a situation, in step S401 shown in FIG. 4, themanagement server 20 sets the management server's operation mode to theregistration mode so as to indiscriminately respond to a request (e.g.,a PXE request).

Subsequently, for example, when the client apparatus 10 is manuallypowered up, the client apparatus 10 transmits a PXE packet for a PXErequest to the management server 20 in step S402.

In step S403, the management server 20 receives the PXE packet from theclient apparatus 10 and the data analyzing unit 23 b in the managementserver 20 analyzes the PXE packet. In step S404, the data analyzing unit23 b obtains a MAC address indicating the transmission source of the PXEpacket and checks whether or not the obtained MAC address is alreadyregistered in the management table 22 a.

Upon confirming that the obtained MAC address is not registered in themanagement table 22 a, the data analyzing unit 23 b in the managementserver 20 transmits an agent to the client apparatus 10 to create a listof the MAC addressees of LAN cards equipped in the client apparatus 10and causes the agent to transmit the created MAC-address list. Uponreceiving the MAC-address list transmitted by the agent, the dataanalyzing unit 23 b sends out the MAC-address list to the MAC-addressregistering unit 23 c.

Upon receiving the MAC-address list from the data analyzing unit 23 b,the MAC-address registering unit 23 c registers all of the received MACaddresses in the management table 22 a in association with thecorresponding client apparatus 10.

After the MAC-address registering unit 23 c completes the registrationof the MAC addresses, as described above, the data analyzing unit 23 bissues a request to the response processing unit 23 d so as to respondto a request from the client apparatus 10.

Upon receiving the response request for the PXE request from the dataanalyzing unit 23 b, the response processing unit 23 d executesprocessing for responding to the request from the client apparatus 10,based on a response procedure composed in accordance with apre-registered request from the client apparatus 10.

For example, in step S405, the response processing unit 23 d refers tothe management table 22 a to transmit, to the client 10, a packetspecifying a procedure description corresponding to the startup ID setin the management table 22 a.

Upon receiving the packet from the management server 20, in step S406,the client apparatus 10 operates in accordance with the startup IDspecified by the packet.

Response Processing:

The flow of response processing performed between the management serveraccording to the first embodiment and the client apparatus will now bedescribed with reference to FIGS. 5A and 5B. As shown, the responseprocessing unit 23 d in the management server 20 composes aprocessing-request procedure so as to cause the client apparatus 10 tooperate, for example, in order of power ON, data backup, rebooting andHDD startup.

For execution of processing for responding to a request from the clientapparatus 10 based on the composed processing-request procedure, theresponse processing unit 23 d first sets the startup ID in themanagement table 22 a to “2” and issues a power-ON instruction set for(1) in the processing-request procedure to the client apparatus 10 instep S501.

Upon receiving the power-ON instruction from the management server 20,the client apparatus 10 is powered up and transmits a PXE packet to themanagement server 20 in step S502.

In step S503, the data analyzing unit 23 b receives the PXE packet fromthe client apparatus 10 and analyzes the PXE packet. The data analyzingunit 23 b obtains a MAC address indicating the transmission source ofthe PXE packet and checks whether or not the obtained MAC address isalready registered in the management table 22 a.

Upon confirming that the obtained MAC address is registered in themanagement table 22 a, the data analyzing unit 23 b issues a request tothe response processing unit 23 d so as to respond to the request fromthe client apparatus 10. On the other hand, upon confirming that theobtained MAC address is not registered in the management table 22 a, thedata analyzing unit 23 b executes the registration processing, asdescribed above (see FIG. 4).

Upon receiving the response-processing request from the data analyzingunit 23 b, the response processing unit 23 d operates in accordance withthe startup ID set in the management table 22 a and responds to theclient apparatus 10 in step S504. That is, the response processing unit23 d issues a data-backup request set for (2) in the processing-requestprocedure, together with a packet to which startup ID “2” set in themanagement table 22 a is added, to the client apparatus 10 via the datatransmitting/receiving unit 23 a.

Upon receiving the data backup request together with the packet from themanagement server 20, the client apparatus 10 performs PXE startup inaccordance with startup ID “2” added to the packet and also executesdata backup in accordance with the backup instruction in step S505. Uponcompletion of the data backup, the client apparatus 10 then transmits abackup completion notification to the management server 20.

Upon receiving the backup completion notification from the clientapparatus 10, the response processing unit 23 d in the management server20 issues a request for (3) rebooting set in the processing-requestprocedure to the client apparatus 10.

Upon receiving the rebooting request from the management server 20, theclient apparatus 10 starts rebooting in step S506. Upon completion ofthe rebooting, the client apparatus 10 causes an agent to transmit areboot notification to the management server 20.

When the management server 20 receives the reboot notification from theclient apparatus 10, the response processing unit 23 d sets the startupID in the management table 22 a to “1” and waits for reception of a PXEpacket transmitted from the client apparatus 10 in step S507.

When a PXE packet is transmitted from the client apparatus 10 to themanagement server 20 in step S508, the management server 20 receives thePXE packet. The response processing unit 23 d refers to the managementtable 22 a and issues a response in step S509 by transmitting, to theclient apparatus 10, a packet to which startup ID “1” set for (4) in theprocessing-request procedure is added.

Upon receiving the packet from the management server 20, the clientapparatus 10 operates in accordance with the startup ID specified by thepacket in step S510.

Advantages of First Embodiment

As described above, according to the first embodiment, the managementserver performs processing for managing communication with each clientapparatus through the network and for responding to a predeterminedrequest received from the client apparatus. In addition, the managementserver pre-stores information (e.g., redundancy MAC addresses) used whenthe client apparatus performs data transmission/reception, inassociation with each client apparatus. Upon receiving a predeterminedrequest from the client apparatus, the management server checks whetheror not transmission-source information (e.g., the MAC address of atransmission source) indicating the transmission source of the receivedpredetermined request is included in the pre-stored information. Uponconfirming that the transmission-source information is not included inthe pre-stored information, the management apparatus obtains, from theclient apparatus that is the transmission source of the predeterminedrequest, all information used when the client apparatus performs datatransmission/reception. The management server then registers theobtained information in association with the client apparatus that isthe transmission source of the predetermined request. Thus, for example,during processing between the client apparatus and the managementserver, even when a LAN card that is currently used by the clientapparatus fails and switching to an inactive redundant LAN card isperformed, the management server can register MAC addressescorresponding to the redundancy LAN cards in the client apparatuswithout suspension of the processing and also can respond to a requestfrom the client apparatus by performing real-time operationcorresponding to the switching between the LAN cards in the clientapparatus.

According to the first embodiment, when the MAC addresses obtained fromthe client apparatus are to be registered in association with the clientapparatus that is the transmission-source of a predetermined request,the data length(s) of the obtained MAC addresses is also registeredtogether with the MAC addresses. Thus, it is possible to register theMAC addresses in a state in which each MAC address can be easilyidentified.

According to the first embodiment, for example, upon confirming that aMAC address indicating the transmission source of a predeterminedrequest is included in the pre-stored MAC addresses, the managementapparatus executes processing for responding to the predeterminedrequest. Thus, for example, even when a LAN card that is currently usedby the client apparatus fails and switching to another redundant LANcard is performed, the management apparatus can execute responseprocessing that corresponds to the request from the client apparatus inreal time.

According to the first embodiment, the response processing is executedbased on a preset processing sequence in accordance with a predeterminedrequest received from the client apparatus. Thus, the managementapparatus can set a startup ID and so on for processing to be executedby the client apparatus and also can smoothly execute responseprocessing that corresponds to the request from the client apparatus.

Although a case in which redundancy MAC addresses used when a clientapparatus performs data transmission/reception are stored has beendescribed in the first embodiment, the present technique is not limitedthereto. For example, the present technique is similarly applicable to acase in which multiple redundancy pieces of information, instead of theMAC addresses, are stored.

Other Embodiments

Although one embodiment of the present technique has been describedabove, the present technique may be carried out in various forms otherthan the above-described embodiment. Thus, other embodiments encompassedby the present technique will be described below.

Apparatus Configuration, Etc:

The elements of the management server 20 illustrated in FIG. 2 aremerely functionally conceptual, and do not necessarily have to bephysically configured as illustrated. That is, the distribution andintegration of the elements of the management server 20 are not limitedto the illustrated configuration, and all or some of the elements can befunctionally or physically distributed or integrated in any form inaccordance with loads, the use state, and so on.

For example, the data analyzing unit 23 b and the MAC-addressregistering unit 23 c may be integrated together. In addition, all orsome of the processing functions accomplished by the management server20 can be realized by a CPU and a program analyzed and executed therebyor can be realized by wired-logic-based hardware.

Communication Management Program:

The processing (see FIGS. 4 and 5) described in the first embodiment canbe accomplished by causing a computer system, such as a personalcomputer or a work station, to execute a prepared program. Thus, oneexample of a computer for executing a communication management programhaving functions that are analogous to those of the first embodimentwill be described below with reference to FIG. 6. FIG. 6 is a diagramshowing the computer for executing the communication management program.

As shown in FIG. 6, a computer 30 serves as a management server andincludes a communication-control interface unit 31, a HDD 32, a RAM 33,a ROM 34, and a CPU 35, which are connected to each other via a bus 40.

The ROM 34 pre-stores a communication management program that providesfunctions that are analogous to those of the management server 20according to the first embodiment, i.e., pre-stores a datatransmitting/receiving program 34 a, a data analyzing program 34 b, aMAC-address registering program 34 c, and a response processing program34 d, as shown in FIG. 6. The programs 34 a, 34 b, 34 c, and 34 d may beappropriately integrated together or distributed, in the same manner asthe elements of the management server 20 shown in FIG. 2. The ROM 34 maybe a nonvolatile RAM.

The CPU 35 reads the programs 34 a, 34 b, 34 c, and 34 d from the ROM 34and executes the programs to thereby cause the programs to act as a datatransmitting/receiving process 35 a, a data analyzing process 35 b, aMAC-address registering process 35 c, and a response processing process35 d, as shown in FIG. 6. The processes 35 a, 35 b, 35 c, and 35 dcorrespond to the data transmitting/receiving unit 23 a, the dataanalyzing unit 23 b, the MAC-address registering unit 23 c, and theresponse processing unit 23 d, respectively in the management server 20shown in FIG. 2.

The HDD 32 stores a management table 32, as shown in FIG. 6. Themanagement table 32 a corresponds to the management table 22 a shown inFIG. 2. The CPU 35 reads management table data 33 a from the managementtable 32 a, stores the read management table data 33 a in the RAM 33,and executes processing based on the management table data 33 a storedin the RAM 33.

The programs 34 a, 34 b, 34 c, and 34 d do not necessarily have to bepre-stored in the ROM 34. For example, the programs may be stored on aportable physical medium (e.g., a flexible disk (FD), CD-ROM, DVD disk,magneto-optical disk, or IC card) to be inserted into the computer 30 ora fixed physical medium (e.g., a HDD) provided inside or outside thecomputer 30 or may be stored on another computer (or a server) connectedto the computer 30 through a public line, the Internet, a LAN, or a WAN(wide area network) so that the computer 30 reads the programs therefromand executes the programs.

According to the present technique, the management server performsprocessing for managing communication with each client apparatus throughthe network and for responding to a predetermined request received fromthe client apparatus. In addition, the management server pre-storesinformation (e.g., redundancy MAC addresses) used when the clientapparatuses perform data transmission/reception, in association witheach client apparatus. Upon receiving a predetermined request from theclient apparatus, the management server checks whether or nottransmission-source information (e.g., the MAC address of a transmissionsource) indicating the transmission source of the received predeterminedrequest is included in the pre-stored information. Upon confirming thatthe transmission-source information is not included in the pre-storedinformation, the management apparatus obtains, from the client apparatusthat is the transmission source of the predetermined request, allinformation used when the client apparatus performs datatransmission/reception. The management server then registers theobtained information in association with the client apparatus that isthe transmission source of the predetermined request. Thus, for example,during processing between the client apparatus and the managementserver, even when a LAN card that is currently used by the clientapparatus fails and switching to an inactive redundant LAN card isperformed, the management server can register MAC addressescorresponding to the redundancy LAN cards in the client apparatuswithout suspension of the processing and also can respond to a requestfrom the client apparatus by performing real-time operationcorresponding to the switching between the LAN cards in the clientapparatus.

According to the present technique, when the MAC addresses obtained fromthe client apparatus are to be registered in association with the clientapparatus that is the transmission-source of a predetermined request,the data length(s) of the obtained MAC addresses is also registeredtogether with the MAC addresses. Thus, it is possible to register theMAC addresses in a state in which each MAC address can be easilyidentified.

According to the present technique, for example, upon confirming that aMAC address indicating the transmission source of a predeterminedrequest is included in the pre-stored MAC addresses, the managementapparatus executes processing for responding to the predeterminedrequest. Thus, for example, even when a LAN card that is currently usedby the client apparatus fails and switching to another redundant LANcard is performed, the management apparatus can execute responseprocessing that corresponds to the request from the client apparatus inreal time.

According to the present technique, the response processing is executedbased on a preset processing sequence in accordance with a predeterminedrequest received from the client apparatus. Thus, the managementapparatus can set a startup ID and so on for processing to be executedby the client apparatus and also can smoothly execute responseprocessing that corresponds to a request from the client apparatus.

As described above, the communication management program, thecommunication management method, and the communication managementapparatus according to the present technique are useful for acommunication management program for causing a computer to executeprocessing for managing communication with client apparatuses through anetwork and for responding to a predetermined request received from eachclient apparatus and also for a communication management method and acommunication management apparatus which implement the communicationmanagement program. In particular, the communication management program,the communication management method, and the communication managementapparatus according to the present technique can operation correspondingto switching between LAN cards in the client apparatus and are suitablefor an application for responding to a request from the clientapplication.

1. A server apparatus connected to a plurality of client apparatusescapable of sending out a message containing environment information tothe server apparatus, the server apparatus comprising: a storage forstoring environment information in association with each of the clientapparatuses; and a processor for receiving a message including updatedenvironment information indicative of addition of an interface deviceconnected to the client apparatus from the client apparatus and forupdating the environment information in the storage with the updatedenvironment information.
 2. The server apparatus of claim 1, wherein theprocessor detects whether the updated information included in themessage is stored in the storage or not.
 3. The server apparatus ofclaim 2, wherein the processor updates when the updated informationincluded in the message is not stored in the storage.
 4. The serverapparatus of claim 1, wherein the processor corresponds to the updatedenvironment information on the basis of a predetermined procedure. 5.The server apparatus of claim 1, wherein the environment information isa MAC address.
 6. The server apparatus of claim 5, wherein the processorassociates the MAC address with the data length of the MAC address.
 7. Amethod of controlling a server apparatus connected to a plurality ofclient apparatuses capable of sending out a message containingenvironment information to the server apparatus, the method comprising:storing environment information in association with each of the clientapparatuses; receiving a message including updated environmentinformation indicative of addition of an interface device connected tothe client apparatus from the client apparatus; and updating theenvironment information in the storage with the updated environmentinformation.
 8. The method of claim 7, further comprising detectingwhether the updated information included in the message is stored ornot.
 9. The method of claim 8, wherein the updating updates when theupdated information included in the message is not stored.
 10. Themethod of claim 7, further comprising corresponding to the updatedenvironment information on the basis of a predetermined procedure. 11.The method of claim 7, wherein the environment information is a MACaddress.
 12. The method of claim 11, further comprising associating theMAC address with the data length of the MAC address.
 13. Acomputer-readable recording medium that stores a computer program forcontrolling a server apparatus connected to a plurality of clientapparatuses capable of sending out a message containing environmentinformation to the server apparatus, according to a process comprising:storing environment information in association with each of the clientapparatuses; receiving a message including updated environmentinformation indicative of addition of an interface device connected tothe client apparatus from the client apparatus; and updating theenvironment information in the storage with the updated environmentinformation.
 14. The computer-readable recording medium of claim 13,wherein the process further comprises detecting whether the updatedinformation included in the message is stored or not.
 15. Thecomputer-readable recording medium of claim 14, wherein the updatingupdates when the updated information included in the message is notstored.
 16. The computer-readable recording medium of claim 13, whereinthe process further comprises corresponding to the updated environmentinformation on the basis of a predetermined procedure.
 17. Thecomputer-readable recording medium of claim 13, wherein the environmentinformation is a MAC address.
 18. The computer-readable recording mediumof claim 17, wherein the process further comprises associating the MACaddress with the data length of the MAC address.